Heated or unheated sapphire?

An unheated sapphire is naturally usable in jewelry, but a heated sapphire is not considered to be “denatured.” An update on this ancestral technique, its advantages and why some people prefer to avoid it.

What is a heated sapphire?

The heating of the sapphire is an extremely common process, carried out in a high-temperature oven (up to about 1,800°C) or in a traditional way. This was already done in Antiquity.

The aim is to improve natural blemishes, inclusions and lack of color intensity or homogeneity. Numerous blue sapphires are naturally of inadequate quality to be used on jewelry, which is in turn too light or too dark. That said, these gemstones exist in different colorss and many of them are heated, for example, the purple sapphire. In particular, better saturation is obtained.

The vast majority of sapphires are heated, regardless of their origin in the world.

What is the price of an unheated sapphire?

Theoretically, Buying an unheated blue sapphire is more expensive than that of a heated sapphire. The same goes for the other colors. An unheated sapphire is rarer and the value is increasing. Some stones are even rarer, such as Unheated Burmese sapphire, of remarkable purity and brilliance. Same for the unheated Ceylon sapphire which, although less rare, is also renowned for its high quality and diversity of shades.

However, the Price of a sapphire does not depend only on heating. The Price of a heated sapphire high quality may well be higher than the price of a less exceptional unheated sapphire.

Is it okay to heat sapphire?

Whether or not there are additives (diffusion treatment), Sapphire heating is a totally accepted practice in the world of jewelry. It is specified on gemological certificates and considered normal, even essential, for many stones, including diamonds or prestigious Burmese rubies. As for precious stones, only emerald cannot be heated.

Heated or unheated sapphire: what to choose?

Buying an unheated sapphire may have advantages, provided the stone is naturally of good quality, of course. Lovers of authenticity prefer sapphires that have not been embellished, look for rarer stones, or collect the higher-value stones. For the creation of rings and jewelry, many people turn to heated sapphires because of the prices or simply because they are easier to find in a variety of shapes and colors. One unheated sapphire ring may require a lot of research.

Can you recognize a heated sapphire?

A gemologist has the necessary equipment to Recognize a heated sapphire from an unheated sapphire. With the naked eye, it's impossible. On the other hand, let's take the example of a pink sapphire, which would be brownish: you can clearly see the difference after heating.

Heating does not denature a sapphire

Heating is not considered to be a treatment per se. That's why A heated sapphire is no less valued than an unheated one. Treatments that can significantly change the nature of stones are more controversial. But if they are mentioned on the certificate of authenticity (which is in fact required by French law), there is no deception. A good example is the treatment called filling, which consists of injecting products into the fractures of a stone, in order to make it more beautiful and solid. This treatment improves appearance, but it affects physical properties.